EUS-guided drainage of Post-Surgical versus Post-Pancreatitis collections (the RESPELL study): A prospective comparison of clinical presentations and therapeutic outcomes

Background: Prospective evidence on Endoscopic Ultrasound-guided drainage (EUS-FCD) for Post-surgical Fluid Collections (PS-FCs) is lacking, and differences from Post-pancreatitis collections (PP-FCs) remain undefined. Methods: All consecutive patients undergoing EUS-FCD with Lumen Apposing Metal Stents (LAMSs) or Double-Pigtail Plastic Stents (DPPSs) between 2020-2024 were included in a prospective registry (PROTECT, ClinicalTrials.gov NCT04813055), with scheduled follow-up exploring efficacy and safety outcomes. Results: At baseline, PS-FCs (N=41) versus PP-FCs (N=45) occupied fewer abdominal quadrants (p=0.04), showed reduced necrotic content (none/≤30% in 68% vs 42%, p<0.05), thus less frequently belonging to the high-risk Quadrant-Necrosis-Infection classifier (24% vs 49%, p=0.02). PS-FCs more frequently presented infection as the drainage indication (68% vs 29%, p=0.0003) and were drained earlier than PP-FCs (35 [17-69] vs 70 [40-200] days, p=0.0004), more frequently adopting DPPSs rather than LAMSs. Step-up (including necrosectomy) was significantly less frequent (20% vs 51%, p=0.002). Technical (100%) and Clinical success (95% vs 93%, p=0.9) were similar, whilst Adverse Events were lower in the PS-FCs (17% vs 40%, p=0.02), and no recurrence was registered (versus 7.5% in the PP group). Conclusions: PS-FCs occur earlier, are more often infected, but display simpler morphology, are more suitable for DPPS drainage, and carry a lower risk of step-up, adverse events, and recurrence.